Users of table saws have long coped with flying sawdust particles by cutting wood outdoors, wearing masks, building makeshift bins, building plastic enclosures around their work area or using canvas bags attached to the underside of the table saw. Cutting wood outdoors is limited by weather conditions which can disrupt work schedules when indoor cutting is not permissible. Moreover, sawdust particles dropping to the ground are easily tracked into living areas of the home and become lodged in carpets and in furnishings where they can create an unhealthy environment. According to the National Institute for Occupational Safety and Health (NIOSH), table saws create a significant amount of wood dust which is known to cause health problems including eye and skin irritation, allergy, reduced lung function, asthma, and nasal cancer. Wood dust is known to be a human carcinogen.
Therefore, a need exists for a sawdust collector that is easily attached and removed from a table saw and permits the user to work indoors without producing significant amounts of sawdust.
A number of products have been designed to collect sawdust generated by table saws. For example, U.S. Pat. No. 4,367,665 issued to Terpstra, et al. on Jan. 11, 1983 discloses a sawdust collector bag detachably connected to and closing the bottom of the base for collecting downwardly directed sawdust, and an elaborate blower and conduit structure for withdrawing fine sawdust through the top of the saw blade guard and from the back side of the table saw. The blower and conduit configuration renders table saws to be difficult to move and essentially non-portable. In typical saw operations, most of the sawdust not dropping straight down, flies straight out across the table in a direct path from the downward circulating saw blade and under the guard at a very rapid rate of speed. Little sawdust flies up into the saw guard because of the direction of the blade's rotation and the location of the wood being cut. If the blade direction was to be reversed, this apparatus may work well but may also render the table saw inoperable. Further, since over 85% of sawdust is directed downward, and most of the remaining 15% leaks through the vents in the base, it is not likely that the blower and conduit mechanism are of any real value. The detachable bag has to be removed to empty the sawdust from it as it is not connected to the motorized dust collector. This unit is very expensive to manufacture.
U.S. Pat. No. 4,489,909 issued to Terpstra, et al. on Dec. 25, 1984 discloses a sawdust collector bag arranged for convenient detachable connection to walls of an open stand using retaining clips. This is essentially the same bag as discussed above for the '665 patent, but with a new means of connecting and detaching the bag from the table saw unit. This bag is floor length and must be removed from the stand and manually emptied.
U.S. Pat. No. 4,576,072 issued to Terpstra, et al. on Mar. 18, 1986 discloses a sawdust collection apparatus which includes a specially formed and hinged, table top saw guard and sawdust collector to which a vacuum hose is connected in a manner to admit air bleeding such that air particles are drawn into the collector while excluding small pieces of wood. The design also includes a deflector mounted on the swinging saw cradle below the table in the saw base for directing sawdust downwardly to a collector bag, foamed synthetic material for sealing various openings in the saw base and a removable bracket for supporting the vacuum hose above the saw table. This apparatus has many parts when in combination collect very little sawdust as noted above with reference to the '665 patent.
U.S. Pat. No. 4,144,781 issued to Kreitz on Mar. 20, 1979 discloses a funnel-shaped flat-bottomed shroud positioned at the rear of the worktable and connects to a vacuum. The collector adjusts along the table base such that it aligns with the saw blade even when doing bevel cuts. This invention is specifically designed for radial arm saws and is not adaptable to table saws.
U.S. Pat. No. 5,582,225 issued to Schank on Dec. 10, 1996, discloses a workbench consisting of a top working surface containing holes that allow sawdust and chips to land in a plenum which slopes to a vacuum connection. The vacuum connection is a bifurcated input manifold allowing the operator to select between applying the vacuum to the plenum or applying the vacuum to a hose containing a vacuum cleaning tool for cleaning the surface of the work bench. A table saw with the stand removed, could be placed on the work bench but the work bench would require a re-design so that the operator could reasonably be able to work close enough to the work surface to make accurate cuts. If a redesign were practical, sawdust particles from the saw would deflect upward off the work bench surface between and around the holes of the plenum.
A product currently sold to the public is the Craftsman Table Saw Sawdust Collection Kit Model 9-29962, is a plastic box type unit, V shaped on two opposing sides designed as a conduit to vacuum hoses. This unit is specifically designed for Craftsman table saws and must be used with a vacuum. It does not have a sawdust drop option and can only be installed and removed by separating the table saw from the stand. It can not be installed into the base of the table saw and must be installed in units having a stand.
A second product on the market is Craftsman item 00922100000 which is a collection bag designed for Craftsman table saws. It attaches to a bracket installed between the table saw and the table saw stand. The dust collection bag must be removed for emptying and does not have a vacuum connection.
A third product on the market is named Less-Mess which is a floor length snap on sawdust collection bag designed for table saws with stands. The sawdust collection bag must be removed for emptying, does not have a vacuum connection and does not have any other means for continuous evacuation of sawdust.
Fine Woodworking Magazine profiled a build-it-yourself sawdust collection system for table saws in its December 2000 issue in an article entitled Dust-Proof Your Contractor's Saw. This device is a plywood box mounted to the underside of a table saw stand, one side of which has a dust port which must be connected to a motorized sawdust collector. The design is very similar to the aforementioned Craftsman Table Saw Sawdust Collection Kit Model 9-29962 but has a back plate for table saws having external motors. While this design requires attaching a motorized sawdust collector to it, it would be possible to use a vacuum adapter to enable the attachment of workshop vacuums. It does not have a sawdust drop option, must be attached to a table saw stand and is not easily removed.